My first feeling is that you have the wrong serial dev for your OBDII device. Are you using bluetooth? USB? Serial? Which /dev entry are you using? Which OS are you on? I support OSX, Linux, and probably others depending on how nicely someone asks.

Can you go to window->raw output and click the checkbox to capture output, *before* clicking "go"? You can leave that window open while you use the main UI. The stuff that I want to see should appear in the right hand pane. Can you paste that here?

It's also worth noting that while debugging and setting up, it may be easier to use the command-line. So long as gpsd is running fine for you, just while testing the only thing you need to do is "./obdgpslogger -t -s /dev/your-obd-device"

To get it to work I have to start another obd program first. Then I start obdgpslogger. I had a similar problem with the obd stuff in the nghost project and I believe it tuned out the developer had to have a longer delay when communicating.

FWIW, I've now added an ATZ at the start in svn. I've also added one in my closeserial function, so hopefully I'm leaving the device in a state so that other software won't exhibit these same problems, no matter what I do in future.